<?php

/**
 * This is the model class for table "{{tag}}".
 *
 * The followings are the available columns in table '{{tag}}':
 * @property integer $id
 * @property string $name
 * @property integer $frequency
 */
class Tag extends CActiveRecord
{
	/**
	 * Returns the static model of the specified AR class.
	 * @return Tag the static model class
	 */
	public static function model($className=__CLASS__)
	{
		return parent::model($className);
	}

	/**
	 * @return string the associated database table name
	 */
	public function tableName()
	{
		return '{{tag}}';
	}

	/**
	 * @return array validation rules for model attributes.
	 */
	public function rules()
	{
		// NOTE: you should only define rules for those attributes that
		// will receive user inputs.
		return array(
			array('name', 'required'),
			array('frequency', 'numerical', 'integerOnly'=>true),
			array('name', 'length', 'max'=>128),
			// The following rule is used by search().
			// Please remove those attributes that should not be searched.
			array('id, name, frequency', 'safe', 'on'=>'search'),
		);
	}

	/**
	 * @return array relational rules.
	 */
	public function relations()
	{
		// NOTE: you may need to adjust the relation name and the related
		// class name for the relations automatically generated below.
		return array(
		);
	}

	/**
	 * @return array customized attribute labels (name=>label)
	 */
	public function attributeLabels()
	{
		return array(
			'id' => 'ID',
			'name' => 'Name',
			'frequency' => 'Frequency',
		);
	}

	/**
	 * Retrieves a list of models based on the current search/filter conditions.
	 * @return CActiveDataProvider the data provider that can return the models based on the search/filter conditions.
	 */
	public function search()
	{
		// Warning: Please modify the following code to remove attributes that
		// should not be searched.

		$criteria=new CDbCriteria;

		$criteria->compare('id',$this->id);
		$criteria->compare('name',$this->name,true);
		$criteria->compare('frequency',$this->frequency);

		return new CActiveDataProvider(get_class($this), array(
			'criteria'=>$criteria,
		));
	}
	
	public function normalizeTags($attribute,$params)
  {
    $this->tags=Tag::array2string(array_unique(Tag::string2array($this->tags)));
  }
  
  public static function string2array($tags) 
  {
    return preg_split('/\s*,\s*/', trim($tags),-1, PREG_SPLIT_NO_EMPTY);
  }
  
  public static function array2string($tags)
  {
      return implode(',', $tags);
  }
  
public function updateFrequency($oldTags, $newTags)
	{
		$oldTags=self::string2array($oldTags);
		$newTags=self::string2array($newTags);
		$this->addTags(array_values(array_diff($newTags, $oldTags)));
		$this->removeTags(array_values(array_diff($oldTags, $newTags)));
	}
	
	public function addTags($tags)
	{
		$criteria = new CDbCriteria();
		$criteria->addInCondition('name', $tags);
		$this->updateCounters(array('frequency'=>1),$criteria);
		foreach ($tags as $name)
		{
			if(!$this->exists('name=:name',array(':name'=>$name)))
			{
				$tag=new Tag();
				$tag->name=$name;
				$tag->frequency=1;
				$tag->save();
			}
		}
	}
	
	public function removeTags($tags)
	{
		if(empty($tags))
			return ;
		$criteria = new CDbCriteria();
		$criteria->addInCondition('name', $tags);
		$this->updateCounters(array('frequency'=>-1), $criteria);
		$this->deleteAll('frequency<=0');
	}
	
	public function findTagWeights($limit=20)
	{
		$models=$this->findAll(array('order'=>'frequency DESC','limit'=>$limit,));
		
		$total=0;
		foreach ($models as $model)
			$total+=$model->frequency;
		
			$tags=array();
			
			if($total>0)
			{
				foreach ($models as $model)
					$tags[$model->name]=8+(int)(16*$model->frequency/($total+10));
				ksort($tags);
			}
			return $tags;
	}
}